That would have been an expensive exercise. BEMO HOm stock doesn't come cheap; engines are generally over GBP £200 to £250 each, and even the tiny coaches are getting on for about £50 each new.
Years ago, I bought a BEMO RhB G4/5, based on the preserved no.108 at Landquart. I felt intense pain handing £320 over the counter. For that reason alone, I have kept it. I will probably arrange for it to be put in my coffin when I die - the model owes me that much!